Such a procedure is known for example from DE 10 2004 005 072 A1.
Reciprocating piston internal combustion engines, which are controlled and regulated electronically by an engine control signal, basically develop pollutants in the form of nitrous gases and particles during the conversion of the chemically connected fuel energy into heat.
In order to filter the particles from the exhaust gas, such combustion engines are provided with particle filters in the exhaust gas system, in which the emitted particles are stored. A high percentage of these particles is combustible, especially particles based on carbon. These are generally termed as soot. After a specific operating time a regeneration of the particle filter is necessary while the stored particles are oxidized. During this process heat is released. This heat release during the regeneration phases muss be controlled and regulated, because of temperature peaks in the particle filter that could otherwise occur and which can have a negative impact on the stability and the overall functioning of the particle filter or even destroy it. For that reason it has to be made sure that a certain inlet temperature of the exhaust gas into the particle filter for the oxidation of the particles is set. For this purpose measures that raise the exhaust gas temperature are provided, for example a postponement of the injection beginning of the main injection to late or the additional fuel injection in the same working cycle after the main injection as so called after injection. Furthermore after initiating the regeneration specific engine operation points in the course of the regeneration shall not be started anymore according to the construction of the exhaust gas after treatment system. During the thermal regeneration of diesel particles the transition into idle or boost operation for example, during which the motor vehicle is not driven by the engine, but rolls on a descent for example due to the conversion of potential into kinetic energy, is harmful to the soot combustion directly after beginning the regeneration or can be even damaging for the system at a very highly loaded filter.
Therefore the procedure that is known from DE 10 2004 005 072 A1 takes advantage of the information data regarding the route for controlling the regeneration cycles, in order to avoid in an anticipatory strategy, that for example a regeneration process of a soot particle filter that lasts over several minutes has to be ended due to adverse engine operating parameters or when it could come to a damage of the after treatment system. It can also be avoided by including the information data that characterizes the route for example, that a regeneration takes place for example in a tunnel, since the bad exhaust gas values of the combustion engine that are usually connected with the regeneration are undesired in a tunnel.
But also at this procedure it cannot be avoided completely that operating statuses of the combustion engine and the motor vehicle occur, which are harmful for a regeneration of the diesel particle filter. Thus for example driving statuses can occur, which do not allow a regeneration or which make an abortion of a regeneration necessary, for example when the vehicle is moving with a higher speed on the autobahn, a driving status, which principally allows a regeneration, but this driving status is abruptly ended by the driver, for example because of a traffic jam.
In systems that are known from the state of the art usually a message occurs in a display in the instrument panel as soon as the system gets into critical statuses that are pre-programmed and stored in the control unit, for example the message to see a mechanic or a hint to seek driving conditions with higher speed.
The invention is based on the task to improve a procedure for regenerating an exhaust gas after treatment system according to the category in such a way, that negative impacts on the exhaust gas after treatment system and the combustion engine are further minimized by complying with exhaust gas values that are as good as possible and by optimizing a regeneration of the exhaust gas after treatment system, whereby also the driving statuses are mostly considered that allegedly cannot be detected and that are harmful for the regeneration.